Slate-splitting tool.



V. F. LAKE.

SLATE SPLITTING TOOL. APPLICATION FILED AUG-2| 1909. RENEWED SEPT. 19. 1915.

2 SHEETSSHEET 1.

Patented June 12, 1917.

INVENTOR W/ TNESSES v. F. LAKE.

SLATE SPLITTING TOOL. APPLICATION FILED AUG.2, I909. RENEWED SEPT. 19, I916.

1,229,622. Patented June 12, 1917.

2 SHEETS-*SHEET 2.

WITNESSES INVENTOR ms ATTORNEX VINCENT F. LAKE, 01? PLEASANTVILLE, NEW JERSEY.

SLATE-SPLITTING TOOL.

Application filed August 2, 1909, Serial No. 510,841.

To all whom it may concern:

Be it known that I, VINCENT F. LAKE, a citizen of the United States, and a resident of Pleasantville, Atlantic county, State of New J ersey, have invented new and useful Improvements in Slate-Splitting Tools, of which the following is a specification.

The invention relates to the art of splitting slaty, schistose, shaly and laminated rocks, and more particularly to tools for splitting such rocks. In certain of its features, the invention relates more especially to tools for splitting slate, although in other of its features it may be applicable to the splitting of other kinds of rocks.

Objects of the invention are to provide a tool which will split slate and other rocks with great speed and expedition; which will act to split the slates into much thinner plates or thicknesses; which will require the expenditure of a minimum of time relatively to the product secured; which will minimize the skill and judgment requisite in the operator; which will further minimize the breakage and other spoiling of the material operated upon. These and other objects of invention will in part appear more fully herein and will in part be obvious to those skilled in the art.

The invention consists in the novel articles, parts, combinations and improvements v herein shown and described.

The accompanying drawings, referred to herein and forming a part hereof, illustrate one embodiment of the invention, the same serving in connection with the description herein to explain the principles of the in- .vention.

Of the drawings:

Figure 1 is a front elevation of a tool constructed in accordance with the principles of the invention, the tool being in position to begin the splitting of a block of slate;

Fig. 2 is a side elevation corresponding to Fig. 1;

Fig. 3 shows the tool and slate block while the splitting operation is in progress;

Fig. 4: is a side elevation corresponding to Fig. 3; I I

Fig. 5 is a top plan corresponding to Figs. 3 and 4; l

Figs. 6 to 9 inclusive, illustrate modified forms of the chisel blades wherein the cutting edges vary in width, relative position of cutting or splitting edges, etc. as will be clear from the drawing;

Specification of Letters Patent.

Patented June 12, 1917.

Renewed September 19, 1916. Serial No. 121,088.

Fig. 10 is a section of a piece of slate having an irregular cleavage plane; and

Fig. 11 is a sectional view on the line A-B of Fig. 10, showing how the flexible blades will follow the irregular cleavage line of the slate.

Referring by way of example to the accompanying drawings, the tool is indicated generally by A. It is shown further in position to begin the splitting of the block S of slate. The edge of the tool A is shown as consisting of a plurality of parts or blades a a a a and 6?. The edges of these various blades are normally in the same plane with respect to each other, but as the blades are of resilient material, or have a resilient action, any one of the blades may be moved or deflected out of such plane with respect to the others. The edges of the respective blades are shown closely contiguous to each other, and the openings or slits between the blades are indicated by a There are also shown openings of in the body of the tool, which may be provided, if desired, to reduce the weight of the tool and to aid in a general way in conferring resiliency thereon.

The tool is provided with suitable operating means, and as the present embodiment is suitable for manual use, the tool is shown provided with a handle a which may be grasped by the hand of the operator. Means are providecL by one feature of the invention for simultaneously imparting energy simultaneously to all the blades. In the illustrated embodiment, the handle is provided with a striking head a which may be struck by a mallet or hammer held in the other hand of the operator, the force of the blow being communicated to all the blades, or to such of them as are in position to perform work upon the block of slate being operated on.

In accordance with one feature of the invention a splitting member is provided having a plurality of splitting blades, each of said blades being itself subdivided into a plurality of smaller blades. This serves to enhance the resilient or flexible action of the blade, which will be found serviceable in some classes of work. This form of splitting member is shown in Fig. 6 of the drawings, the blades being designated as a a, a, a and at. These blades are separated by the openings or slits a The smaller, or subsidiary blades, are formed by the slits or openings at in the blades just referred to.

In accordance with one feature of the invention, the blades constituting the cutting edge are normally in the same plane with each other, as already described, but the edges of all of the blades do not lie in the same straight line in said plane. In other words it may be found advantageous in working with certain kinds of slates'and other rocks, to have some of the blades longer than others. That is, certainof the blades will enter the slate first and start the line of cleavage at separated points and other blades located intermediately with respect to these will enter theslate just subsequent thereto. This will serve to correct any tendency to deviation of the line of cleavage between the blades which had first entered the slate, and at the same time the tool enters the slate with an easier action by reason of the lesser number of blades entering at one time. In Fig. 7 of the drawings a tool A is shown in which the blades are arranged with a longer blade 04 in the center and with relatively shorter blades a and (4 on either side thereof. The blades a and a may have their edges in line if desired. The width of the blades relatively to each other may also be varied as may be found desirable in working upon different kinds of rocks. In Fig. 7 the blades a and (L are shown narrower than the blade at.

In Fig. 9 of the drawings a tool A is shown having a plurality of blades, with the outer blades a and a longer than those next to them, which are designated a and a. There is also shown in this figure a central blade (L which is likewise longer than those next to it.

In Fig. 8 of the drawings a tool A is shown embodying in one tool certain of the features and principles set forth in other figures of the drawings. In said figure we have the blades of different lengths and relative flexibility, that is, the blades which consist of subsidiary blades as they havebeen termed, and also the blades of the different relative lengths.

It will be understood that the changes in form shown herein are illustrative in their character and not restrictive of the scope of the invention set forth in the claims.

The manner of using the invention will be described in connection with the splitting of slate. Slate does not have to have a pronouncedlaminated structure, such as that of mica. That is, it does not possess laminae which are separate and well defined. It may be said rather to possess a grain or fiber which causes it to cleave or split in a certain definite direction. Thus it may be split into comparatively thin sheets or plates. Therefore, in a general way by proper experienced handling, it is possible to cleave a sheet or plate from a block of slate which will be of substantially uniform thickness throughout.

The cleaving action, however, follows what may be called the plane or direction of least resistance, and thus it often happens that the first insertion of a chisel begins a split which would run out of the desired plane toward one of the faces of the block of slate. Owing to this tendency in the slate, with the implements at present in use the exercise of considerable skill and judgment, as well as the expenditureof considerable time, are necessary on the part of the operator.

For purposes of elucidation, it may be consideredthat it is desired to split a rectangular block' of slate alongthe median line of one of its ends. In the art as heretofore practised, the operator places an ordinary small chisel on the end of the block and near its center after which he gives it a gentle blow with his mallet to develop the line of cleavage. In case the cleavage runs to either side of the median line, the operator places the chisel at various points along the end of the block so as to establish the median line across it, striking light blows with the mallet at each position, thus establishing a plurality of small cleavage planes which break into each other; After these operations a slight crack appears across the entire end. It will thus be seen that the various short lines of cleavage established tend to merge into each other and thus overcome the tendency of the first established line of cleavage to depart from the median line, and to approach either face of the block.

After this artificial line of cleavage, as it may be called, has been extended across the end of the block, the chisel is driven into said line near the middle of the block to a depth of an inch or so and then a pryin'g movement is imparted. to it by the hand of the operator to split the block in two. The thinner the block, and consequently the thinner the plates into which it is divided, the more difficult is this operation. It often requires the use of a number of chisels of difierent lengths, inserted at various parts of the cleavage line, and also requiring that blows of carefully regulated force be distributed on the chisel at different times in a manner known only to. a skilled operator. The cleavage planes in slate are seldom true, are frequently disturbed by hard spots, and the. elasticity of the slate also varies greatly. It therefore, takes years of practical experience to become a skilful slate splitter with the old tools and by the old method. Even then the waste from breakage is relatively large.

With a tool constructed in accordance with the principles of the present invention, the plurality of blades will establish the median line at a large number of points simultaneously, as shown in Figs. 1 and 2,

and by a single blow upon the striking head a. This serves at once to establish a plurality of lines of cleavage which will break into each other, forming one continuous line across the end of the block, and thus overcome any tendency of the slate to part along a line of cleavage coincident with one of the blades but at other points deflecting away from the medianline and toward either face of the block.

As the splitting progresses, and a hard spot such as 8 shown in the block of slate S in Fig. 4 is encountered, which is very difficult of cleavage, as the remainder of the slate splits more readily, while it hangs together at said spot, almost all cleaving action of the blades elsewhere will cease for the time being, and the force of the blows delivered to the tool will be absorbed by the particular blade or blades encountering the hard portion until it is cut through. Then all the blades will resume their cleaving action. No watchfulness by the operator to apply a chisel to the hard spot .9, or to bestow extra blows at that point will be required as heretofore practised, for as already explained a blow given to striking head a would be communicated directly to the desired and eifective point. It will be clear that there is a great saving of time and labor in the operation, as well as less necessity for great skill.

It frequently happens that there are irregularities in the lines or planes, if they may be so called, of cleaving as shown at Figs. 10 and 11. That is, they remain parallel but all deviate together from a true plane. It is then desirable and necessary in order to save the slates that the splitting follow such deviation. With a tool having the series of flexible blades, as shown in the present invention, the blades are permitted to follow such slight irregularities, one blade yielding or moving relatively to the other transversely to their common plane (as shown in Fig. 11), thus maintaining the plate or block on each side of practically uniform thickness. This is a consideration of prime importance in splitting thin blocks. It will thus be seen that there is a great saving of time and also lessening waste of material over the former methods.

From all the foregoing it will be understood that a tool has been provided realizing the objects of invention and the advantages herein set forth, together with other objects and advantages. It will be understood also Copies of this patent may be obtained for that the invention is not limited to the specific forms herein shown, but that variations may be made therefrom within the scope of the claims.

What I do claim as my invention and desire to secure by Letters Patent is:

1. A slate splitting tool including a plurality of blades having their splitting edges arranged substantially in the same plane, said blades being resilient transversely to said plane.

2. A slate splitting tool including in combination a plurality of resilient blades with their splitting edges in substantially the same plane but the edge of one of said blades being in advance of the edge of another of said blades.

3. A slate splitting tool having a plural ity of blades arranged in the same plane, said blades being of different sizes, and also being resilient transversely to said plane.

4:. A slate splitting tool having a plurality of splitting blades arranged side by side, one or more of said blades being longer and wider than the others, said blades being transversely flexible relatively to each other.

5. A slate splitting tool having a plurality of splitting blades arranged side by side, the inner blades being wider than the outer and having their splitting edges arranged in advance of the splitting edges of the outer edges, said blades being transversely flexible relatively to each other.

6. A slate splitting tool including a plurality of blades having their splitting edges arranged substantially in the same plane, said blades having a common mounting, said blades being resilient transversely to said plane, and a non-resilient energy transmitting head.

7. A slate splitting tool having a plurality of resilient blades, said blades in turn consisting of a plurality of longer and shorter blades.

8. A slate splitting tool including in combination a flat body of resilient metal, a striking head thereon, a plurality of flexible splitting blades formed on said body, said blades being in substantially the same plane but varying in width and length.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

VINCENT F. LAKE.

Witnesses:

JOHN D. MORGAN, Ross MENK.

five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

